Material of choice for non-invasive treatment of dentin caries: An in vitro study using natural carious lesions

Introduction: In community settings with limited dental personnel and equipment, and in an era when the aerosol transmission of infectious agents is on the rise, a non-invasive approach to caries management is critical. To provide information on non-invasive material selection, the aim of this study was to compare the remineralization effect of commonly used fluoride-containing materials, adjunctive to the everyday use of fluoride toothpaste (F-toothpaste), on primary tooth natural dentin caries.

Methods: Fifty-five specimens were randomly divided into five groups: 38% silver diamine fluoride (SDF), 5% fluoride varnish (F-varnish), glass-ionomer cement (GIC), deionized water (DW) with F-toothpaste slurry, and DW as a control group (n = 11). The lesion depth and mineral density were measured before and after bacterial pH-cycling using micro-computed tomography. The percentage of mineral density change (%MDchange) was quantified. The dependent t-test, Wilcoxon-Signed-Rank Test, and one way ANOVA with Bonferroni correction were used to analyse the data.

Results: SDF application reduced lesion depth from 844.6 to 759.1 μm (p < 0.045) while increasing mineral density from 551.4 to 763.0 mgHA/cm³ (p < 0.003). Only mineral density rose from 600.2 to 678.4 mgHA/cm³ (p < 0.013) when GIC was used. The other groups showed no difference. The highest %MDchange was also found after SDF treatment (49.7%, p < 0.05), whereas GIC (17.2%, p < 0.05) presented a higher percentage than the F-varnish (2.0%), F-toothpaste (-1.1%) and no-treatment groups (-1.4%).

Conclusion: In this in vitro study, where the pH of cycling was almost neutral, using SDF as an adjunct to F-toothpaste resulted in the highest remineralization compared with other remineralizing materials.